0,2

Write n in base 3, then (working from left to right) if the k-th digit of n is equal to the corresponding digit to the left of the k-th digit of a(n) then this is the k-th digit of a(n), otherwise the k-th digit of a(n) is the element of {0,1,2} which has not just been compared, then read result as a base 3 number.

Index entries for sequences that are permutations of the natural numbers

a(n) =3a([n/3])+((-a([n/3])-n) mod 3) =3a([n/3])+A060582(n) with a(0)=0.

a(46)=76 since in base 3 43 is written as 1201; this gives a first digit of 2(=3-1-0) for a(n), a second digit of 2(=2=2), a third digit of 1(=3-2-0) and a fourth digit of 1(=1=1); 2211 base 3 is 76.

Cf. A060586, A060587.

Sequence in context: A039814 A160201 A078301 this_sequence A078104 A072280 A086054

Adjacent sequences: A060580 A060581 A060582 this_sequence A060584 A060585 A060586

base,nonn

Henry Bottomley (se16(AT)btinternet.com), Apr 04 2001